The present invention is directed to a straight knitting machine having two needle beds and knocking-over combs arranged in an inverted V-shape configuration for knitting without the application of takeoff tension on the knitted piece and devices to locate the stitches beneath the needle crossover zone with such devices being mounted on the sliding carriage for movement relative to the needle bed.
In conventional straight knitting machines having two needle beds and knocking-down combs arranged in an inverted V-shaped configuration, a tension is applied to the knitted piece during knitting so that the stitches or loops depending from the needles slide on them under pressure. As a result of such tension, the previously knitted piece will not be pushed upwardly as the needles are advanced outwardly of the slots in the needle bed so that the tongues of the needles are properly opened and closed by the stitches or loops. After the stitches or loops are knocked-down over the closed needles, the newly formed row of stitches is pulled downwardly between the two needles beds by means of the tension on the previously knitted piece. The tension on the knitted piece is provided by take up rollers operatively located beneath the needle beds.
The disadvantage of such straight knitting machines is that the tension on the center of the knitted piece is different from the tension on the edges of the knitted piece. Furthermore, it is not possible with such straight knitting machines to produce knit-goods where the knitting is not always effected over the entire width. Thus, it is not possible to save material or to knit the correct shape when simultaneously knitting individual knitted parts since, in this instance, groups of needles on the needle bed are not knitting for several rows or the stitches are popped off these needles. In order to permit this type of stitching, straight knitting machines were developed in which a wire, fastened to the sliding carriage, runs beneath the needle crossover zone to prevent the knitted piece which is not tensioned from being lifted above the knocking-over combs of the needle beds by means of the activated upwardly moving needles. Complicated devices are then required which swivel and turn and which are shifted, lifted and lowered at the end of each knitted row so that the wire will take the proper position for knitting the following row without additional lost motion of the sliding carriage. Furthermore, the hold down effect provided by such wire could only be achieved in the case of knitted pieces being produced simultaneously on both needle beds, that is, with double knitwear but not with the production of single knitwear.
A straight knitting machine of the type described above is, for example, disclosed in German publication 1956190. In this machine, the stitches can only be held beneath the needle crossover zone with the passing of the sliding carriage by means of frictional contact. A device on the sliding carriage of the straight knitting machine is disclosed in German Utility Patent 7795391 which has a wire bracket acting as a stripping, holding and layering device with the passing of the sliding carriage. Separate stripping and holding devices are disclosed in Austrian Patent 214050.